Sole-sewing machine.



J. R. SCOTT.

SOLE SEWING MACHINE.

APPLICATION FILED can 13, 1913.

88,,18w Patented July17, 1917.

3 SHEETS-SHEET l.

J. R. SCOTT.

SOLE SEWING MACHINE.

APPLICATION man em 13. 1913.

Lmm 5513 0 Patented July 17, 1917.

3 SHEETS-SHEET 2.

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Wimwwci f fizz/6223507" J. R. SCOTT.

SOLE SEWiNG MACHINE.

- APPLICAT|0N FILED OCT-13,1913.

Patented July 17, 1917.

3 SHEETS-SHEET s.

JACOB R. SCOTT, OF NORTH WEYMOUTH, MASSACHUSETTS, ASSIGNOR TO UNITED SHOE MACHINERY COMPANY, OF PATEBJSON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

SOLE-SEWING MACHINE.

Specification of Letters Patent.

Patented July 1'7, 1917.

Application filed October 13, 1913. Serial No. 794,858.

to which it appertains to make and use the same.

This invention relates to sole sewing machines, and more particularly to solo sewing machines of the McKay type.

In sole sewing machines of the McKay type the needle actuating mechanism is usually constructed and arranged to pro duce variations in the position of one of the limits of the needle stroke to correspond with changes in the thickness of the work so that the length ofthe loop drawn out by the needle above the work in the formation of each stitch will always be substantially the same, regardless of the thickness of the work. In McKay sole sewing machines at present in common commercial use, to produce the required variations in the needle stroke a needle actuating mechanism is provided in which there is lost motion between the needle bar and its actuating mechanism at the end of each stroke of the needle, which motion is terminated by limiting stops, the

, position of one of which is controlled by the vertical position of the presser foot as determined by the thickness of the work so as to vary the retracting stroke of the needle. In these machines a friction block is provided to engage the needle bar and i the upward movement of the needle is arrested chiefly by the frictional resistance of the friction block. Considerable momentum is acquired by the moving parts during the retracting stroke of the needle and the action of the friction block is uncertain so that the needle often retracts beyond the normal limit of its upward stroke or overthrows, causing imperfect work, particu' of its variable limit at substantially the normal limit of its stroke, regardless of the length of the stroke.

With the above objects in view, the inventlon comprises various novel features clearly set forth in the following descrip- 131011 and pointed out in the claims, the advantages of which will be obvious to those skilled in the art from the following description.

In the drawings illustrating a machine embodying the invention in its preferred form;

Figure 1 is a view in front elevation of the machine; Fig. 2 is a view in side elevation of the machine looking from the left. Fig. 3 is a view in side elevation of the inachine looking from the right; and Fig. 1 is a detail sectional view illustrating the presser bar and a portion of the mechanism by which it is actuated and controlled.

The machine illustrated in the drawings is a straight hook needlechain stitch sewing machine of the McKay type and comprises a vertically reciprocating straight hook needle 1, secured 'to the lower end of the needle bar 2, a cast-0E 3, a presser foot 41 mounted on the lower end of the vertically movable presser bar 5 and a feed point 6.

The work is supported during the sewing operation by a vertically fixed rotatable horn, the tip of which, shown at 7, contains substantially the same as in the machine illustrated and described in the patent granted to the present applicant, No. 1,050,568, January 14;, 1913. The cast-ofi is secured to the lower end of a bar 9 arranged in a groove in the needle bar which has a lateral projection 10 extending through a slot in a plate 11 and the bar is held in po sition with relation to the plate with the projection 10 at the lower end of the slot by a spring 12, the ends of which are engaged respectively in holes in the projection and plate. The plate 11 hasa second slot 13 in which operates a lug 1 1 projecting from a block 15 attached to the needle bar. The cast-oflt is moved vertically by the engagement of the lug 14 with the ends of the slot 13. The cast-off is held stationary during the first part of the stroke of the needle bar in each direction by a friction device 16.

The needle bar 2 is mounted to reciprocate vertically in guides in the upper and lower plates 17 and 18 of the head of the machine and 'is connected by means of a link 19 with the forward end of an actuating lever 20 pivoted on a stud 21 carried at the upper end. of, a fulcrum. post 22. The lever 20- is oscillated about its. fulcrum to reciprocate the needle by means of, a crank 23 carried by the main shaft 24 of the machine and connected with the rear-end of the lever QO by a pitman 25. The fulcrum post has a rising and falling movement between; limiting; stopswhich allows the needle to dwell respectively at the end of its stroke in each direction. The stop which limits the upward movement of the fulcrum post is fixed soqthat the'needle always descends to the same point during its downward stroke while the position. of the stop, which limits the downward movement of the fulcrum post is controlled from the presser foot so that the upi'vard' stroke of the needle is varied as the work varies in thickness. The rising movement of the fulcrum post islimited by the engagement of' a clamp. nut 26 threaded on the lower end of the post with the lower plate 18. The falling-movement of the fulcrum post is limited by the engagement of the head of a screw bolt 27 carried by the horizontal arm 23 of a sleeve 29 mounted on the fulcrum post with a stop 30 formed 011 a lever-31 pivoted at its rear end on. the stud 32; The forward end of the lever 31 engages the upper face of a shoulder 33 on the presser bar so that the vertical position of the lever and of the stop 30 is controlled by the vertical position of the presser foot. The sleeve 29 is held against the stop 34: fixed on the fulcrum post by a spring 35 coiled about the post and interposed between the sleeve and. an adjustable clamp -n.nt on the post. This spring allows the fulcrum post to yield downwardly just before i the needle begins its upward stroke to obviate any sudden jerk upon the thread. and to prolong the dwell of the needle. A friction block 36 engages the needle bar and holds it stationary during the movements of the fulcrum post.

To prevent overthrow of the needle during its retractingstroke, in the construction illustrated, a block 37 is attached to the needle bar and extends rearwardly therefrom into position to engage the under side of a block or slide 38 mounted to slide vertieally on a vertical post 39 secured at its ends in the upper and lower plates of the header the machine. The slide 38 is yieldingly pressed down by a coiled spring 40 surrounding the post 39 and interposed between the upper face of the slide and the plate 17. As the needle bar approaches the end of its normal upward stroke, the block 37 engages the lower face of the slide 33 and carries the slide upwardly therewith against the resistance of the spring -l(). The spring is thereby compressed and acts together with the friction of the friction block to check the upward movement of the needle bar immediately upon its release from the action of its actuating mechanism. It is undesirable that the block 37 engage the slide 33 throughout any considerable portion of the upward stroke of the needle bar since when the slide is engaged and moved by the block the force ofthe spring 40 furnishes considerable resistance to the upward movc ment ofthe needle bar. -Inorder that the slide may be engaged by the block only during the last part of the upward stroke of the needle bar and at substantially the same distance from the normal limit of upward stroke of said bar regardless of the height to which the needle bar moves, a rod -11- rarried by the slide 38 is connected with the lever 31 by means of a screw pin 12, passing through, a vertical slot- 43 in the lower end of the rod. During each cycle of operations of the machine the presser foot is lifted away from the horn to allow the work to be fed as the needle is executing the latter part of its upward stroke. As the presser foot is lifted, the pin 42 strikes the upper end of the slot 43 and t-heslide 38 is lifted with the presser foot to a position such that the block 37. will engage the under side of the slide just before the needle reaches the normal limit of its upward stroke. The presser foot is lifted the same distance in each cycle of operation and the height to which it is lifted varies with the thickness of the work so that the height to which the slide 38 is carried by the lifting of the presser foot varies with the thickness of the work and with the changes in the upward stroke of the needle. The slide is therefore engaged by the block substantially the same distance from the end bf the normal upward stroke of the needle whether thc stroke of the needle is relatively long or short.

The rod 41 is vertically adjustable in a. bore in the slide 38 and is held in adjusted position in the slide by means of the nuts '11 threaded on the rod and engaging the upper and lower faces of the slide. By changing the vertical position of the rod -l-1 with rclation to the slide the point at which the block 37 engages the slide with relation to the limit of the normal upward stroke of the needle and the distance through which the slide is moved by the block will be varied. The provision for adjustment of the rod. therefore, enables the action of the mechanism to be regulated so that the spring will furnish just the required resistance to ill) stop the upward movement of the needle bar at once upon its release from the action of its actuating mechanism.

It is obvious that if so desired the rod 41 may be so adjusted with relation to the slide 38 that the block 39 will engage the slide just as the needle reaches the limit of its normal upward stroke.

The presser bar 5 is mounted at its upper and lower ends in suitable guides. The presser foot is held yieldingly in contact with the work by means of a spring 45 coiled about the presser bar and interposed between a fixed abutment and a collar 46 on the presser bar. The downward movement of the presser bar when no work is in the machine is limited by an adjustable block 47 mounted on the upper end of the presser bar and arranged to engage a fixed abutment 48. The mechanism for lifting the presser foot during each cycle of operations comprises a nut 49 mounted on the presser bar and engaging a series of'screw threads 50 of steep pitch formed on the bar, a block 51 for engaging the nut to lock the nut from rotation on the presser bar, and mech anism for lifting the block to raise the nut and the presser bar. The nut when not engaged by the block 51 is free to turn on the presser bar, so that it ofiers no resistance to the rising and falling movements of the bar. The nut is supported by an arm 52 project ing from a sleeve 53 mounted on a vertical rod 54 at the rear of the presser bar. A spring 55 coiled around the rod and interposed between the upper end of the sleeve and a fixed abutment acts to force the sleeve downwardly. The downward movement of the sleeve under the force of the spring 55 is limited by an adjustable stop nut 56 mounted on the rod. The arm 52 supports the nut 49 by engaging in a groove in the nut, which groove is wide enough to permit a limited longitudinal movement of the nut independent of the arm. The block 51 is mounted to slide freely on the presser bar below the nut and is provided with lateral projecting pins 57 upon which blocks 58 are mounted. These blocks are received in slots in the forked forward end of an actuating lever 59 pivoted at 60 011 the frame, the rear end of which is provided with a roll 61 engaging in a cam groove formed in a cam disk mounted on the main shaft 24. The upper end of the block 51 is formed with a slightly tapering friction surface 62 which is adapted to engage a corresponding friction surface 63 formed on the inside of the nut 49. When the block 51 is raised it engages the nut 49 and lifts it independently of the arm 52 until the lower surface of the groove in the nut engages the arm. During this movement of the nut independent of the arm the pressure of the engaging friction surfaces of the block and the nut is slight and the nut rotates on the presser bar 5. During the continued upward movement of the block the arm 52 and the sleeve 53 are raised with the nut 49 and the spring 55 forces the friction surfaces together with a heavy presthere is substantially no lost motion of rotation between the block and the nut thereafter, the presser foot is always lifted a certain and uniform distance. During the downward movement of the block 51 the presser bar is depressed by theaction of the spring 45 and the nut is held in engagement with the block by the spring 55 acting on the nut supporting sle we 53 until the downward movement of the sleeve having been arrested by the stop nut 56, the upper surface of the groove in the nut engages the arm 52, thereby arresting the downward movement of the nut, or until the presser foot engages the work. Then, as the block 51 continues its downward movement, the friction surface on the block is disengaged from the corresponding friction surfaces on the nut, allowing the nut to turn freely on the presser bar, the presser foot then being held yieldingly in engagement with the work by the spring 45 and accommodating itself to the thickness of the work.

Having explained the nature and object of the invention and having specifically described a machine embodying the same in its prefererd form, what I claim is 1. A chain stitch sewing machine, having, in combination, stitch forming devices including a straight hook needle, a needle bar, mechanism for reciprocating the needle bar having a period of lost motion at the end of the stroke of the needle in each direction, means for varying the limit of the stroke of the needle in one direction as the work varies in thickness, a work support, a resser-foot, means independent of the needle mechanism for relatively moving the work support and resser-foot during each cycle of operations, a movable abutment for preventing overthrow of the needle bar during its movement in the direction of its variable limit, and means acting automatically to vary the position of said abutment in accordance with changes in the stroke of the needle.

2. A chain stitch sewing machine, having in combination, stitch forming devices ineluding a straight hook needle, a needle bar, mechanism for reciprocating the needle bar having a period of lost motion at the end of each stroke of the needle, means for vary- .ing the limit of one of the strokes of the needle as the work varies in thickness, a work support, a presser-foot, means independent ot the needle mechanism for relatively moving the work support and presserfoot during each cycle of operations, a movable yieldingly supported abutment for preventing overthrow of the needle bar dur ing its stroke in the direction of its variable limit, and means acting automatically to vary the position 01" said abutment in accordance with changes in the stroke of the needle.

3. A chain stitch sewing machine, having, in combination, stitch forming devices including a straight hook needle, a needle bar, mechanism for reciprocating the needle bar having a period of lost motion at the limit of the retracting stroke of the needle, a vertically fixed work support, a vertically movable presser foot, means independent of the needle mechanism for lifting the pressertoot during each cycle of operations, means controlled by the work engaging position of the presser foot for varying the retracting stroke of the needle as the work varies in thickness, a movable abutment for preventing overthrow of the needle bar at the end of its retracting stroke, and a connection between said abutment and presser foot for varying the position of the abutment in accordance with changes in the retracting stroke of the needle.

4. A chain stitch sewing machine, having in combination, stitch forming devices including a straight hook needle, a needle bar, mechanism forreciprocating the needle bar having a period of lost motion at the end of the stroke of the needle in each direction, means for varying the limit of the stroke of the needle in one direction as the work varies in thickness, a work support, a presser-toot, means independent of the needle mechanism for relatively moving the work support and presser-foot during each cycle of operations, an abutment carried by one of the moving parts, a movable abutment for engagement with the first abutment during the stroke of the needle in the direction of its variable limit to prevent overthrow of the needle, means for varying the position of the second abutment at the time that the abutments are brought into engagement in accordance with changes in the stroke of the needle in the direction of its variable limit so that the abutments will be engaged through a uniform portion of the stroke of the needle, regardless of the length of the needle stroke.

5. A chain stitch sewing machine, having in combination, stitch forming devices ineluding a straight hook needle, a needle bar, mechanism for reciprocating the needle bar having a period of lost motion at the limit of the stroke of the needle in each direction,

means for varying the limit of the stroke of the needle in one direction as the work varies in thickness, an abutment carried by one of the moving parts, a movable abutment for engagement with the first abutment during the stroke of the needle in the direction of its variable limit to prevent overthrow of the needle, means for varying the point at which the abutments are engaged in accordance with changes in the stroke of the needle in the direction of its variable limit so that the distance through which the abutments are engaged is constant, regardless of the length of the stroke of the needle, and provision for adjustment to vary the point at which the abutments are engaged with relation to the normal limit of the needle stroke.

6. A chain stitch sewing machine, having in combination, stitch forming devices ineluding a straight hook needle, a needle bar, mechanism for reciprocating the needle bar having a period of lost motion at the limit of the retracting stroke of the needle, a vertically fixed work support, a vertically movable presser foot, means controlled by the work engaging position of the presser foot for varying the retracting stroke of the neodle as the work varies in thickness, an abut ment carried by one of the moving parts, a movable yieldingly supported abutment for engagement with the first abutment to prevent overthrow of the needle bar at the end of its retracting stroke, a connection between said abutment and presser foot for varying the position of the second abutment in accordance with changes in the retracting stroke of the needle bar so that the abut mcnts will be brought into engagement at a constantdistance from the normal limit of the needle stroke regardless of the length of said stroke, and provision for adjustment to vary the point at which the abutments are brought into engagement with relation to the normal limit of the needle stroke.

7 A chain stitch sewing machine, having in combination, stitch forming devices including a straight hook needle, a needle bar, a work support, a presser toot, mechanism for reciprocating the needle bar having a period of lost motion at the limit of the retracting stroke of the needle, a block carried by the needle bar, a vertically adjustable spring pressed bloek in the path of the first block to engage therewith and prevent overthrow of the needle bar during its retracting stroke, a rod adjustably connected with the spring pressed block, and a connection between the lower end of the rod and the presser foot whereby the spring pressed block is lifted as the presser foot is raised from the work.

8. A chain stitch sewing machine, having in combination, stitch forming devices including a straight hook needle, a needle bar, mechanism for reciprocating the needle bar having a period of lost motion at the end of each stroke of the needle, means for varying the limit of the stroke of the needle in one direction as the Work varies in thickness, a Work support, a resser-foot, mechanism independent of the needle mechanism for relatively moving the Work support and presser-foot during each cycle of operations, means inactive until the needle is adjacent the end of its stroke in the direction of its variable limit for arresting the movement of the needle bar, and mechanism for causing said means to act initially when the needle is at a constant distance from the limit of its stroke regardless of the length of the stroke.

9. A chain stitch sewing machine, having in combination, stitch forming devices including a straight hook needle, a needle bar, mechanism for reciprocating the needle bar having a period of lost motion at the end of each stroke of the needle, means for varying the limit of the stroke of the needle in one direction as the Work varies in thickness, means inactive until the needle is adjacent the end of its stroke in the direction of its variable limit for arresting the movement of the needle bar, mechanism for caus- Gopies of this patent may be obtained for five cents a ll ing said means to act initially when the needie is at a constant distance from the limit of its stroke regardless of the length of the stroke, and provision for adjustment to vary the point at which said means begins to act with relation to the normal limit of the needle stroke.

10. A chain stitch sewing machine, having, in combination, stitch forming devices including a straight hook needle, a needle bar mechanism for reciprocating the needle bar having a period of lost motion at the end of the stroke of the needle in each direc tion, means for varying the limit of the stroke of the needle in one direction as the Work varies in thickness, a Work support, a presser-foot, an abutment movable independently of: the presser-foot for preventing the overthrow of the needle bar during the stroke of the needle in the direction of its variable limit and means acting automatically to vary the position of said abutment in accordance with changes in the stroke of the needle.

J AOOB R. SCOTT.

each, by addressing the Commissioner of Patents.

Washington, D. G. 

